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Why is benzal chloride not written as benzal dichloride...? while we write benzotrichloride?

I need the appropriate reason.

Answer 1

Here is my guess for the reason.

These are both names that were used before systematic names were assigned.

Benzal chloride is prepared from benzaldehyde according to the reaction

I would guess that, since the #"C"_6"H"_5"CH="# group is found in #bb("benzal")"dehyde"#, it was natural to call the compound #bb("benzal")color(white)(l)"chloride"#.

Benzotrichloride is made by chlorination of toluene.

Presumably, the common group #"C"_6"H"_5"-"# group reminded the early chemists of benzene so they coined the name #bb("benzo")"trichloride"#.

The early names weren't very systematic and often the first person to discover a compound got to name it.

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Answer from HIX Tutor

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